I am not an energy Rater .. I am an architect

I am curious if any "Home Energy Pros" make an effort to locate the Neutral Pressure Plane (NPP) of a house that is being blower door tested?

Views: 2711

Reply to This

Replies to This Discussion

Don, I agree, I agree,

As for actually pointing to an elevation and saying the NPP is about here, somewhere in one of these posts I explained how to do that and it is rather easy.  All that is necessary is a ▲t and a manometer.  From inside and outside temperatures, a stack pressure per foot can be calculated.  Then, by taking a high or low pressure reading (that's where the pressure will be the largest) through the envelope, you have it.  If the front door reading is 2pa and you had calculated a 0.25pa per foot stack pressure, then the NPP is 8' above the penetration at the front door.

If you want to get fancy and you have a good ▲t, you can open a window a measured amount and, just like the "add a hole" process for pressure diagnostics, you can estimate the CFM50.  I keep baiting people with this in hopes that someone will do the math for me :).  My to-do list it too long.

As for the metal capillary tube, you can't get too small as a manometer does require a flow of air.  I would have to ask to be sure.  Just an FYI.

Bud

PS, I have started another thread to get into this issue a bit more: http://homeenergypros.lbl.gov/forum/topics/controlling-passive-air-...

RSS

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.

Latest Activity

Rob Madden, Solar Home Broker commented on Alicia Hobbs's blog post 5 Solar Facts that You Should Know
"From personal experience, that $20,000 savings over 20 years will be a low number based upon the…"
3 hours ago
Rob Madden, Solar Home Broker posted a blog post

Phoenix Solar Home Sales Jump in September

The number of solar home sales in Phoenix jumped 13.6 percent from the previous month, according to…See More
3 hours ago
Profile IconGina M., Brian J. Mulhern, James Tucker and 2 more joined Home Energy Pros
5 hours ago
Casey Gesell replied to Trip Smith's discussion Where to spend my marketing dollars?
"Trip, Check out our sister company Contractor Nation: https://www.contractornation.com/ Pay Only…"
5 hours ago
Casey Gesell posted a discussion

Looking for home improvement companies to join our dealer network!

My name is Casey Gesell and I'm the Business Development Manager at Dr. Energy Saver, Inc.Dr.…See More
5 hours ago
Casey Gesell replied to Trip Smith's discussion Starting a Home Weatherization Business. Considering it...
"Hi Trip, Check out our website: www.drenergysaverdealerships.com "
5 hours ago
Alicia Hobbs posted a blog post
5 hours ago
Mark Wozniak posted a status
"I am looking for energy efficiency software training in Massachusetts."
8 hours ago

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service